Marine tower and method of placing same



June 10, 1947. G. L. KlRBY 2,422,168

MARINE-TOWER AND METHOD OF PLACING SAME Filedv Oct. 23, 1945 4Sheets-Sheet 1 June 10, 1947. G. L. KIRBY MARINE TOWER-AND METHOD OFPLACING SAME Filed oct. 23, 41945 4 sheets-sheet 2 June 10, 1947. G.KIRBY MARINE TOWER AND METHOD OF PLACING SAME Filed oct. 23, 1945 4Sheets-Sheet 3 June 10, 1947. G. L. KIRBY 2,422,168

MARINE TOWER AND METHOD OF PLACING SAME 'l Filed oct. 23, 1945 4Sheets-sheet 4 HPPRox cEN TER aF 6R19 YITY poses whichrequire a supportthat is positioned Patented June 10, 1947 UNITED STATES PATENT OFFICEMARINE TOWER AND METHOD F PLACING SAME George L. Kirby, Houston, Tex.,assignor to Kirby .Development Corporation, San Antonio,` Tex.,

a corporation of Texas Application October 23, 1945, Serial No. 624,023

22 claims. l

in and above water.

Heretofore, marine towers (whether assembled to their full length onshore or on a barge) and the methods of placing them, of which I haveknowledge, have been such as required flotation tion to the desiredlocation. This is a hazardous` operation, particularly if storms orrough water are encountered. Furthermore, with this type of handling, atower is liable to be distorted or damaged to a material extent, eventoits total loss. In addition, such an operation requires the use ofexpensive and elaborate equipment, such as barge derricks, etc.,y Inother types of towers, the methods of placing them in position on thewater-bed include the iiotation of a tower base to a location, sinkingit to the water-bed and then erecting thel tower vertically from thebase. These towers also require the use of complicated devices andmechanisms, including divers, and, in some instances, caissons.

The important and principalv object of the present invention is theprovision of a tower of such design that it may be readily assembled, ina horie/ zontal position, on shore and, which, when assembled, iscapable of being floated, in a horizontal position, to the locationwhere it is to be erected and placed on the water-bed. Consequently,lthe necessity of costly erection equipment is eliminated and a minimumof offshore operation is required, thereby eliminating, or greatlyminimizing, the hazards of distortion of, or of severedamage to, thetower during transportation tothe point of location. It is desirablethat the tower be provided with floodablebuoyant devices, by means ofwhich it may be'erected to a vertical position whereupon it can be somanipulated as to settle upon the desired spot on the water-bed where itis to be anchored. By means of these same floodable, buoyant devices,the tower may subsequently be raised and moved to a new location, or itmay be completely salvaged.

It is also an importantobject oi.' the invention to provide a marinetower construction that comprises a plurality of spaced columns whichare or transportation of the towers in a vertical posi-v f disposedconcentrically about a center opening so that .the tower willbesubstantially circular in cross'section with a central, unobstructedshaft extending from the ,top to the bottom thereof. Furthermore, thetower is preferably composed of a multiplicity of interchangeablesections, each comprising sections of the spaced columns, the end of thecolumns of adjacent sections being removably secured together' and thecolumn sections of each tower section being held in position by verticaland horizontal bracing so as to make 'each tower section a unitarystructure, but, nevertheless, without obstructing the hollow shaft inthe center of the tower.

Another .object of the invention resides in the` provision of a towerbase which is annular in form, and upon which the columns rest, the basebeing so designed and proportioned that loads are distributedlconcentricaily and equally on the bedbottom, the base being a hollow,watertight, buoyant member that is connected with standard equipment forflooding or blowing out the same as desired.

A further object of the invention is to provide a tower' having reducedresistancev to external forces,such as to water current and wind presfsure', by forming the columns and bracing thereof with exterior"surfaces which are rounded or circular in cross section.

Another feature of .the invention is the provi'- sion of hollow, buoyantmembers, other than the base members, disposed along the length of thetower, at least one being positioned so as to be at or about, butpreferably a slight distance below,

the normal low water line of the tower, when the latter is resting onthe water-bed. Another hol- "opening so as to cooperate in forming thepaslowybuoyant member may be disposed adjacent the base of the towerwhen it isdesired to supplement the function ofthe base, either forproviding added buoyancy or addedweight, when the base is'or is not tobe flooded, for settling or fixing the tower in position or removing ittherefrom. There may be other and intermediate hollow, buoyantk membersemployed if desired or required. All of these buoyant members arecircular or polygonal in shape and have a center sage or shaft whichextends vertically through the tower.

A stilll further object of the invention is to provide a Ysectionaltower of the above described character that permits the readyremoval or addition of sections as may be required according to ,placed,or according to the work to be performed.

. as it appears when in position in the water;

Figure 2 is a cross sectional view' taken substantially on line 2-2 ofFigure 1;

Figure 3 is a crosssectional view taken substantially on line 3-3 ofFigure 1;

Figure 4' is a cross sectional view taken substantially on line 4--4 ofFigure 1;

Figure 5 is an enlarged fragmentary side view in elevation lof one ofthevertical columns and the bracing `rods associated therewith for rigidlyuniting the several sections of the tower;

Figure 6 is a cross sectional view taken substantially on line 6-6 ofFigure 5;

Figure 7 is a cross sectional view, similar to Figure 6, illustrating achannel pipe chase on one of thel bracing rods;

Figure 8 is an enlarged cross sectional view, similar to Figure 2, withparts broken away to illustrate the construction of the supporting basefor the tower;

Figure 9 is a cross sectional view through the base and is takensubstantially on line 9-9 of Figure 8;

Figure 10 is a cross sectional view taken substantially online IIJ- I8of Figure 9;

Figure 11 is a side view in elevation'of the tower in position on afloating scow from which it is launched;

Figure 12 is an end view in elevation of the tower andscow illustratingthe manner of re- A of the body of water; and,`

Figure 15 is a cross sectional view through the scow and illustratingthe compartments therein, one of which is adapted to be flooded forlaunch-il ing the tower and thereafter blown out.

As shown in Figure 1 of the drawings, the present invention comprises amarine tower I6 which is made up of a series of sections I1. Thesections are supported one above the other and the entire frameworkformed by these sections is carried on a base I8. Merely for the purposeof giving an indication of the proportions of the tower hereinillustrated in Figure 1, thebase is \about 66 feet indiameter and fivefeet high with a central opening of about 46 feet in diameter; and thesections I1 are each approximately 25 feet in length or height and about60 feet in diameter. Of course, it will be understood that thesedimensions are given only by way of example and that they will bechanged or varied according to changes in design or construction thatmay be desirable or required under varying circumstances and conditions.

'I'he base I8, as more clearly illustrated in Figures 2, 8, 9 and 10, isringlike and it may have polygonal sides or it may be a true annulus. As

shown, said base comprises top and bottom plates I9 and 28 and sideplates 2| and'22 which may be welded at their meeting edges. The basehas a hollow, watertight interior to provide a floodable, buoyant memberor chamber I8' and I nay-y accommodate any suitable type of reinforcingstructure that will distribute the imposed vertical load thereonconcentrically of the base. It is reinforced by a multiplicity of spacedcross beams 23 which form supports for the girders or eye beams 24 whichare arranged in parallel relation andcoextensive longitudinally with theWalls Aof the base. Cross channel members 25 rest on the beams 24 atintervals, preferably, adjacent the ends of the beams 24. These members23, 24

and 25 are secured together by suitable means,"

such as welding as one example.

Stub columns 2B are arranged in spaced relation on the top plateIS-preferably over these cross vmembers 25-and the upper end of each issealed by a circular plate I9a welded thereto and extending beyond theperimeter thereof to form a iiange for receiving the pipe column of thelowermost section of the tower framework. A plurality of spaced rcuttingbars 28, attached to the bottom plate 28, are adapted for scouring aseat or bearing for the base structure on the bed of the water as thetower is brought into position.

From the above description of the base, it will be seen that the base isso designed that the imposed loads 4are directly over the bearing andthat there has been provided a stiiened and reinforced watertight casingto form the base. These reinforcing elements are so designed andproportioned that loads are distributed concentric with the columns ofthe tower, andthe center portion of the base is open to permit multipledrilling or other operations, or the erection of various structures. Inorder to provide access to the interior'of the base, one or moremanholes 28 have been provided in the top plate I9, and they may beclosed by suitable watertight covers, not shown.

The base I8 may be used for adding buoyancy to the tower structure, orfor adding weight thereto when positioning said structure on the bedofthe body of Water. 29 extends from the base to a control point Yin theupper end of the tower. and is employed for flooding or venting the basewhen occasion demands or, in some instances, for supplying concrete tothe interior of the base` for increasing the weight and stability of thebase when it has settled in position, In order to provide buoyancy,water is pumped from the base to the control point in the tower.

As previously indicated, the shaft of the tower f upper and lower endsof each pipercolumn carryv a connecting member to which is attachedvertical and horizontal struts. These members also provide means foruniting the sections by the use of bolts or the like. I

Referring particularly to Figure 5 of the drawings which shows theconnected adjacent ends A Consequently, a pipe of the apex portion ofsaid triangular plate-.36.

, The extending ends of the triangle 36 form lugs which have openingstherein through which horizontal brace members may besecured.

The ilange-formingportions of the plates I9a and 34 and thecorresponding area of the plate 36 are designed to engage in abuttingrelation and each is provided with a circular series of matched openingsto receive bolts 45 which secure the adjacent ends of aligned rcolumnsections together as well as the stub columns 26. Triangular vanes 31and 3.9 extend upwardly from the plate 34 and downwardly f'rom the platemember 36 as well as radially relative to their respective columnsections 32, and each has one edge thereof welded or otherwise securedto its pipe section 32, as indicated at 38 and 40, respectively, andeach may also be welded or otherwise xed to the plates 34 and 36,respectively.

Bracing rods 4I are attached to the vanes 31 and 39 and are preferablydiagonally disposed so as to cross one another, as shown in Figure l ofthe drawings, for vertically bracing adjacent column sections of eachtower section. These bracing rods are shown as being provided withadjusting turn-buckles 42, rods 43 extend from the lug 36a on one column32 to a similar lug in an alternate column and are secured thereto bybolts 43a. This arrangement of the horizontal bracing rods is moreparticularly shown in Figure 3 of the drawings; and said rods are alsoprovided with adjustable turn-buckles 44. Additional horizontal struts45 extend between and connect with adjacent lugs 36a by means of bolts46.

Thus, the vertical bracing rods 4I, horizontal bracing rods 43, and pipestruts 45, together with the vertical pipe columns 32, make up eachsection I1 of the shaft of thetower and the sections are joined togetherby bolts ,41, as indicated in Figure 5 of the drawings, which passthrough the plates 34 and 36. While the rods 4 I and 43 are shown asbeing adjustable, they may be fixed, non-adjustable rods and they may bewelded in place. It is to be noted that the column section 32, and thebracing rods 4I, 43 and 45 are each circular in cross section so as toreduce their resistance to external forces, such as Water currents andwind pressures,

Another feature of the invention resides in the use of chambered orhollow buoyant members lixedly positioned within the tower structure,and preferably on opposite sides of its centerof gravity, whereby saidstructure may be floated horizontally, manipulated to vertical position,and lowered to its site with a minimum of effort and equipment. Thesemembers may also be used for raising the tower. For purposes ofillustration, two such buoyant members 48 and 49 have been shown inFigure 1 of the drawings. These buoyant members 48 and 49 are,preferably, identical and, by referring toFigure 4 of the draw-7 ings,it will be noted that they are placed and held, respectively, within thevertical pipe columns 3,2 of the tower section I1 andare secured infixed position therein by any suitable means.

'I'he ybuoyant member 48 is preferably positioned considerably below theupper end of the tower, that will support the platform |80, shown in`dotted line, and rides partially above the? water surface so as tosupport the tower afloat in fits upright position before the tower issunk to rest upon the water-bed. The buoyant member 49 may be placed inany desiredposition, but

, i. e., substantially doughnut-shaped-to provide Horizontal bracing ian unobstructed and'unrestricted work area or shaft that will permitmultiplev drilling from a rig or derrick IUI supported on the platform|80, or for other operations, through the entire length of the tower I6.

Each buoyant member 48 and 49 is connected l with ooding and ventingpipes 5I and 52 termi-f nating at a controlpoint or station 3l havingcontrol valves 3Ia and at which station a subplatform may be providedfor such station and for other auxiliary apparatus, including the"Christmas tree, upon completion of the drilling of the wells. Thebuoyancy of the members 48 and 49 may -be selectively controlled by themeans just described-that is to say, water may be admitted through thepipes 5I, respectively, to said members 48 and 49 and any air thereinmay-be vented from said members through the pipes 52; and, water thusadmitted may be forced out of said members through pipes 5I by admittingair under pressure to said members through pipes 52.

As is to be understood, valves, pumps, and blow out equipment of knownstandard design and for flooding and emptying any of the buoyant membersI8', 48 or 49, are provided at the control station 3I 'and/or thecontrol station may be connected to similar equipment located at aremote point-.say for instance, on a barge or tug which is standing|`ny-all of which is well-known in the art. Inasmuch as the detailedconstruction of said equipment is no part ofthe present invention, noillustration thereof has been made beyond a general designation there asshown. A pipe chase 53 extends upwardly from the base I8 through thetower structure for the protection of the pipes 29 and 30, 5I and 52,which extend, respectively, from the buoyant base I8 and the buoyantmembers 48 and 49.

The uppermost section 54 of the shaft or tower I 6 is provided withconventional hoisting Windlass means 55 to which are connected chains orcables 56 that may also be connected to anchors, not shown, and whichrun over idler rollers 51 which are preferably positioned on the towerI6 at,y or slightly below, the water lever 61. 'The lower ends of thesecables or chains are to be i connected to suitable anchors, notshown,which have been previously set on the water-bed 66 at spaceddistances around,v and remote from, the

site selected for the base I8. While the tower is being located andpositioned on the bed of the body of water, the calbles` or chains areselectively slackened or tightened to adjust and maintain' the tower I6to and in a perpendicular position during the period of positioning and,afterwards, for adding to the stability of the tower and to aid inmaintaining the same in a vertical position in times of extreme stress.

Inl accordance with the present invention, the tower is to be erected onshore and, by reason of its simple design, necessity of costly erectionY equipmentis eliminated. l When placing the tower, for example, inwater up ,to iifty feet in depth where the chambered base I8 and one,two or three sections I'I- (of about 25 feet each 1n length or height)comprise the tower I6, theV umns 32 above the center of gravity take theY place Yof the buoyant member 48 and greatly aid in placement'of thetower. During the sinking operation, the more'the chambered base I8 isflooded, the more the sealed columns tend to keep the tower iny anupright position. Of course, if

desired, a buoyant member 48 ofl appropriate dimensions .may be usedwith a tower comprising a base and three or more sections, either forfloating the tower in upright position to location or in a horizontalposition and for controlling its placement in position.

For .towers made up of more than three sections and the'base, there isshown in Figures 11 to 15 inclusive of the drawings, one method oftransportation. This method is used where certain considerations orproblems prevent towing afloat the entire buoyant structure to the pointof location of its placement. `In such case, it will be seen that thereis employed a scow'58 for transporting a relatively high or long tower,the interior of which barge or scow is hollow and dividedlongitudinally,. as at 58a, to' provide 4a pair of control compartments59 and 60,`from which'extend pipes 6| and 62, respectively. The Y deckof the barge is provided with transversely extending skidways 63, andskids 64 to the tower by means of the cables 65.

l With the tower in position on, and secured to, the barge 58, saidbarge' is Ythen towed to the desiredsite or location in the water. Inorder toV release the tower from the barge, the tower is unsecuredtherefrom andthe compartment 59 thereof is iiooded through the pipe 6I,causing the barge to assume the position shown in Figure 13 of thedrawings. At this time, through the medium of the skids 63 and 64, thetower will be launched sidewise in a horizontal position. The buoyancyof the control members 48 and 49 and the base I8 will allow the towertoride in a hori-` zontal position, though partly submerged.

After launching from the barge, the tower may be floated to the areawhere it is to be positioned.

Then, by iiooding the lower buoyant members 49 Y and/or I8, thertowerwill assume an upright position, as shown in Figure 14. The huppercontrol v, buoyant member 48 is designed so that when it is empty 'itwill carry or support Ythe entire dead load of theV structure and willbuoy the tower so that it willremain slightly above the bed 66 of thebody of water 61. In this position, the tower may be manipulated intoplace over the desired spot on the bed 66upon which it is to rest.Subsequentcontrolled floodingof the upper buoyant member 4.8 (and of thebuoyant member 49 if not completely flooded, or ofthe buoyant basememare attached i ber I8) causes'the tower. to settle slowly onto thebed 66. Y f

movement imparted to the tower will cause the Vlil cutting bars 21'to-s'cour a seat for the base I8 When resistance of 4the Y' structure incontact with the-water-bed prevents further movement, the tower ismaintained in a as the tower settles.

vertical position by adjustment ofthe control cables 56 and by thevcontrolled iioodingV of the buoyant membersV I8, 48 and 49, which'may beY ooded to the extent required to provide suilcient weight to preventthe ebase of the Atower from creeping. Whenthere is no -motion of thewater,

l5 or the consistency or characterof the bedY 66 is such that thescouring process is insufllcient to provide a suitable seat,;otherpractical means,

such as aV hydraulicjet, may beV tain a proper bearing. Y l

VWhile the invention'may be practiced without employed-to obthe columns32 of the frameworkbeing hollowv Y and sealed, the employment of thisfeature'in combinationY withV the other ieatures of this invention hasmany advantages-'among which are. (l) providing a strong structure witha minimum of surface subjected to corrosive elements and (2) the hollowsealed columns contribute to the buoyancy of the structure, by reducingits spef cific gravity, and, when sinking the tower to the Y water-bedwhile in vertical position, furnish that necessary buoyancy desirableto' control the po' sitioning of the tower, thus permitting the controlbuoyant member 48 to beV of smaller size and dimensions resulting inless cost.

Consequently, referring to Figure 14, with the columns 32 hollow andsealed, the buoyant mem-V ber 48 is computed and designed, with respectto the weight of the entire tower, to Vhave an excessdisplacement overtheamount necessary for net buoyancy-i e., tosustain afloat 'the entirewith the base chamber I8 and/or the buoyant dimension or area' A* (Fig.14) Vrepresents the l gross displacement; dimension B represents,dis-VIV placement to sustain said dead load; and dimen- V sion CrepresentsY the excess displacement for iv estimated weight, but lessthe brroyancy afforded l by the sealed columns 3,2.

Therefore; in computing the displacement of thebuoyant member 48, thearea or dimension VE ofthe tower (above the waterline) is computed atits full weight while the portion/or area D (below the'waterline in Fig..14) is figured at apj proximately of its full weight, Vdue to thespecific gravity being about l-to 8, whereby the rso structuralmembersof the submerged portion of \\the towerlose t/g of their weightbyfdisplacement Y which is a gain of about 100 poundsin buoyancy,

per linear foot submerged (with the tower'as Vat Vpresent designed), andto which is tobe added the net air spaces within the sealed columns32fvamounting (in the tower as atpresent designed) `to Vabout 9.6 cubicfeet or approximately 600 Y poundsperY linear foot of the submergedportion ofthe tower, thus making a total of about 70 `700 pounds perlinear foot submerged.

Now, with the tower as shown in Fig. 14 .haveY ,ing either or both ofthe buoyant chambers' I 8' and 49 ilooded and with buoyant member 48empty, the bottom of the base In water having a certain degree ofmotion,the

dead load of the tower as shown in' Figure 14 erected and positioned in'place. Io this end, the" control of the tower and to allow for`variations in" I8 maybe esti'Y mated to be about 15'feet (distance F)above the water-bed 66, or in any event, above the point on which it isto iinally rest, and the tower will be sustained afloat in that positionwith the dimension C of member 48 above the water surface. When it isdesired to sink the tower further, the dimension B of the buoyant member48 will be flooded-to an amount equal to the dimension C-as indicated bythe line C. In other sinking and this is provided by the captive air insealed columns 32 in the dimension E above the waterline. In View of theabove computations, which have been used by way of example, the towernow may be sunk further for a distance of one foot for every 700 poundsof water admitted to the buoyant member 48 (over and above the amount C'that has been already admitted). Consequently, when F' (the dimension ofthe tower above the waterline and corresponding to the distance Fbetween the base I8 and the waterbeen admitted to the member 48, inaddition to the amount C', the tower base will be on oradjacent thewater-bed 66 but will be still suspended aoat by enough buoyancy to keepany pressure oil the base I8 of the tower.

The operation of the proper valves at station 3|, or at other remoteplaces, will stop this sinking movement at any time and at anystage,and, conversely, will initiate sinking or,by blowing out the member 48,raise the tower to selected levels. While so suspended, the motion ofthe tower due to surface motion of the water, will agitate the tower sothat water will be squeezed or compressed in and out of the spacebetween the base I8 and the water-bed 66, causing loose material to beobliterated and, inthe case of heavy material, the cutting bars 21 willbreak said material loose to be washed out. Eventually, there will benothing but bare soil or a bearing surface conforming to theunder-surface of the base I8. As previously stated,lwhen there is nosuch surface motion of the water which will agitate the tower, hydraulicjets may be employed where necessary.

It will be appreciated that a very small amount of water admitted to orblown out of buoyant member 48, under the conditions above mentioned,

.will give an appreciable amount of control.

When a seat or bearing surface for the base has .bed 66) multiplied by'700 pounds of ,water has been thus made and the base seats itself propyerly, the control valve at the station 3| will be open wide to flood thebuoyant member 48 completely which, of course, puts the full load of thetower on the water-bed 86. During the time ofn setting the tower, theupright position of the latter is controlled by means of the Winches 55most section I1 to conform to any use to which the tower may be put. Inthe illustrated embodiment of the invention, a. wide clear working spacehas been provided down through the center of the shaft or tower fordrilling .any convenient number of wells. orfor other purposes.

If for any reason it is desired to remove the tower to another locationor" to recover the same,

complete salvage may be effected by reversing the method employed inpositioning the tower on the bed of the body of water.

For the purposes of the following claims the terms "buoyant mem r" orbuoyant members may refer to either t e base chamber I8'lor the members48 or 49; and the term at or adjacent the base, which deines thedisposition of certain of the buoyant members, shall refer to and meaneither or both of theparts I8 and/oi` 48.

To summarize some of the advantages of the tower, according to thepresent invention, the tower- 1. May be transported'in ahorizontal'position, either in the water, where it floats partiallysubmerged, or on a barge or scow from which it is discharged in ahorizontal position to'fioat;

2. May be used in any water location or marshy location;

3. May be transported and positioned without the requirement ofspecially constructed equipment', thus eliminates costly erectionequipment;

4. Requires a minimum of offshore operation in placing and putting intouse;

5. Provides its own base and means of securing' same on bottom of bodyof water or in marshy locations;

6. Provides means for scouring its seat securing a firm seating orbearing for seating itself on bottom of bed or other location;

7. Has full salvage possibilities;

8. May be constructed and erected to any desired height (within designlimits, which will vary) by adding like sections of interchangeableparts and sections;

9. Has its framework and base arranged-so as to provide open andunobstructed space within lframework and base full length of tower andase;

10. Reduces resistance-of external forces to a minimum;

, 11. Has its base formed by a reinforced structure designed andconstructed to support and distribute the weight of the load of thetower, platform and the load placed on platform;

12. Has itsI base enclosed to form a watertight floodable chamberedbuoyant member that may increase the weight and stability of the towerby flooding said member with concrete after the tower is in position; y

13. Has buoyant members fixed within certain sections, equipped withmeans for flooding and blowing out for controlled buoyancy, and spacedin such manner as to facilitate controlling, floating, sinking, raising,scouring, placing and anchoring tower, and may be used for storage orother purposes while tower is in use;

14. Ha's sections I1, and parts thereof, interchangeable with eachother;

15.' Has-sections I1 individuallybraced horizontally, transversally,cross-braced.' and vertically, so as to provide an unobstructed interiorwork shaft throughout length of tower;

16. Has controllable control-buoyant-members fixed and within frameworkof tower that do not obstruct the open work shaft or space within thetower;

17. May have other control-buoyant-members added as desired ornecessary; 18. Has hollow, sealed, air-containing supporting columns, orlike members, in its framework that reduce the specific gravity of thetower and increases .the controll of the tower in sinking or raisingsame and that furnish added buoyancy at regular intervals about andthroughout the length of the tower;

19. May be anchored by means of guy chains and anchor means whichprovides and allows greater control and safety;

20. Provides means of overcoming, or avoiding, l

creeping or shifting of the base;

21. May be seated, or set, by hydraulic jet when necessary;

22. Is more economical to construct and place than other devices forsimilar purposes; and

23. Is a single unit, composed of interchangeable sections, and partsthereof, a base and other buoyant members.

Obviously many modifications and operations of the invention asVhereinabove set forth may be made without departing from the spirit andscope thereof, and therefore only such limitation should 'be imposed asare indicated in the appended claims.

What I claim as new is: Y

1. A fioatable structural marine tower, to rest on a water-bed andextend above the surface of the water to support a superimposed loadrthereupon, comprising a hollow annular-like water- I tight casingforming a buoyant base to rest upon the water-bed, an open framework tosupport said superimposed load and extending from said base and arrangedabout the central opening in said base, and means for controllablyflooding and emptying said base; said framework and` the opening in saidbase defining an unobstructed open-work-area or shaft extending thelength of the tower to allow multiple drilling operations through thecenter` of the tower.

2. A floatable structural marine tower adapted to rest upon a water-bedand comprising a framework to support superimposed loads and includingan annular-like base to support said framework upon the water-bed, a xedcontrollable buoyant member within said framework and disposed at apoint remote from the base to aid in positioning said tower; said base,buoyant member and framework being arranged to denne a central workspace or shaft extending therethrough-longitudinally of the tower.

3. A floatable marine tower adapted to rest upon a water-bed to supporta superimposed load thereupon comprising a hollow annular-like base,v

a framework secured to and extending from said base and disposed aboutthe central opening in said base, annular-like buoyant means carried bysaid framework and spaced from saidbase, the opening in said base andbuoyant means being in substantial alignment, controllable meansconnected with said base and buoyant means for se- `lectively floodingand emptying said base and buoyant means when floating or positioningsaid tower.

4. A fioatable marine tower adapted to rest upon a water-bed to supporta superimposed load thereupon comprising a hollow annular-like base, aframework secured to and extending from said base and including aplurality of hollow sealed columns, containing captive air, disposedabout the length of the tower to at least its estimated waterline,annular-like buoyant means carried by nected with said base and buoyantmeans for seleotively flooding and emptying said base and buoyant meanswhen fioating or positioning said tower.

5. In a structural marine tower comprising an annular-like base defininga central work opening therethrough, a framework extending verticallyfrom said base when the tower is in upright position, said frameworkbeing arranged relative to the opening in said base to define a centralworkarea longitudinally of the tower, said base including a watertightcasing embodying means for distributing the vertical load imposedthereon concentrically throughout the base, the interior of said casingbeing hollow for buoyancy, and other buoyant means disposed on the towerat a point or points along said framework.

6. In a floatable structural marine tower to rest on a water-bed andextend above the surface of the water to support a superimposed loadthereupon, a hollow annular-like watertight casing forming a buoyantbase to support the tower upon the'water-bed, a framework to supportsaid superimposed load and extending from said base and includingbearing columns that are hollow. and sealed and containing captive air,to decrease the specific gravity of the structure and increase thecontrol of the structure when in water, and that extend the length ofthe tower at least to its, estimated water line and that are Aarrangedat intervals and secured to said base,

, intervals about saidopening in said base, means the central opening insaid base and extending l water.

uniting said columns to define a central work space or arealongitudinally of said tower, a controllable buoyant-means carried bysaid tower, and means for controllably flooding and emptying saidbuoyant means. y,

8. A structural marine tower as set forth in claim 7 furthercharacterized by the base being polygonal or circular-like and saidcolumns being arranged substantially concentrically of said base, aboutthe opening in said base, and saidbase including a stiifened watertighthollow casing forming a controllable buoyant means.

9. A structural marine tower including a base, a, framework extendingvertically from said base, said framework formed of a multiplicity ofsuperimposed interchangeable sections, said base comprising a stiifenedwatertight casing the interior of which is hollow for buoyancy, andcutting bars secured to the bottom face of said base to aid inpositioning said tower on the b'ed of a body f 10. A structural marinetower including a circular-like base, a framework extending verticallyfrom said base, said framework formed of a multiplicity of superimposedinterchangeable sections, said base comprising a stiffened watertightcasing the interior of which is hollow for buoyancy, controlled meanswithin said tower to permit location and settling thereof in a body of iwater, and cutting bars secured to the bottom face of said base to aidin positioning said tower on the bed of a body of water.

11. A structural marine tower comprising a base, a tower frameworkextending vertically from the base when the tower is in uprightposition, control buoyant members, at least one of said members being ator adjacent the base and at least another disposed adjacent the normalor estimated lower-water line of the tower when erected into position,and means connecting said buoyant members to instrumentalities forcontrollably flooding the same or for removing the water therefrom,whereby the tower. may be floated into position and be permitted tosettle and to rest in a vertical position with its base on the bed of abody of water.

12. A structural marine tower comprising a hollow watertight base, atower framework extending vertically from the base when the tower is inupright position, said framework comprising a multiplicity of columnsdisposed substantially concentrically about the center of the base, oneor more chambered buoyant members disposed at intervals along the lengthof the tower to provide buoyant means for floating the tower tolocation, and means connecting said buoyant member or members and said`base to instrumentalities for controllably flooding the same or forremoving the water therefrom whereby the tower may be floated intoposition and be permitted to settle and to rest in a vertical positionwith its base on the bed of a body of water.

13. A structural marine tower comprising a base, a framework extendingfrom the base and formed of a plurality of superimposed interchangeablesections, each of said sections including columns arranged substantiallyconcentrically about the base, and bracing means for said columns, oneor more control chambered buoyant members disposed between said columnsand said bracing means of certain of said sections, and means connectingsaid buoyant member or members to instrumentalities for controllablyiiooding the same or removing the water therefrom, whereby thetower maybe floated horizontally into position, manipulated to a verticalposition and be permitted to settle and to rest in a vertical positionwith its base on the bed of a body of water.

14. A structural marine tower, adapted to rest upon the bed of a body ofwater and extend above the surface of said body of water, comprising aunitary framework including a plurality of supporting columns, saidcolumns being hollow to provide buoyancy t the structure, buoyantchambered members disposed along the l.length of the tower, at least oneon each side of the center of gravity of the tower, whereby the towermay be floated horizontally to location where it is to be positioned,means connecting said buoyant members to instrumentalities forcontrollably flooding the same and for removing water therefrom, wherebyupon flooding of one of said buoyant members, the tower will becomeupright in the water and suspended afloat over said location and, then,by admitting water to the other of said buoyant members, the tower maybe sunk and manipulated to settle andl rest upon the water-bed in avertical position.

15. A structural marine tower as set forth in claim 14 wherein, when thetower is, in said upright suspended position, the buoyant capacity ofthe upper buoyant member, in combination with the buoyancy of saidsubmergedhollow columns, being sufficient to sustain the structureaiioat in an upright position with a portion of the columns extendingabove the waters surface, the buoyancy of said columns beinginsufficient to float said structure when said buoyant member isrendered non-buoyant, the buoyancy of said upper member being controlledby said instrumentalities and when rendered non-buoyant to a degree thatbalances with the load, the buoyancy of the columns above said upperbuoyant member affords such buoyancy sufficient to support the towerafloat, whereby further admission 4 of water to said upper buoyantmember results in nicety of control of the aoat position of tower forsetting the tower and scouring a seat for itself before resting on saidseat on the water-bed.

16. In a floatable structural marine tower to rest on a water-bed andextend above the surface of the water to support a superimposed loadthereupon, a hollow annular-like watertight casing forming a buoyantbase to support said tower upon the water-bed and having a central workopening therethrough, a framework to support said superimposed load andextending from said base and including hollow sealed bearing columnscontaining air and arranged at intervals about said opening in andsecured to said base and bracing for said columns, and means forcontrollably ooding and emptying said base, the framework and theopening in said base defining an unobstructed work area or shaftextending the length of th'e tower to allow multiple drilling operationsthrough the center of the tower.

17. The method of positioning a marine tower in place ona water-bed,which tower comprises a framework with at least two controllablechambered buoyant members, one on each side of the center of gravity ofthe tower, said method including floating the tower in a horizontalposition to the point of location where the tower is to be erected, thenooding one of said buoyant members to bring the tower to an uprightposition and supporting the same in that position by the other of saidbuoyant members, then controllably flooding the said last-mentionedbuoyant member to allow the tower to settle downwardly to rest upon thewater-bed.

18. The method of positioning a marine tower in place on a water-bed,which tower comprises a framework with a base end and a controllablechambered buoyant member carried by the tower p and positioned on theside of the center of gravity of the tower opposite that of the base endof the tower, said methodincluding supporting the tower afloat in a bodyof water in an upright positioniby said buoyant member with the base endof the tower above the water-bed, and controllably flooding said buoyantmember to sink the tower so that its base end will contact but not besupported by the water-bed, whereby surface motion of the body of waterwill cause the base end of the tower to form a bearing seat on thewater-bed, and then further flooding said buoyant member to bring thebase endv of the tower to rest on the water-bed.

19. The method of positioning marine towers in place, which towers maybe built-up on land or on a oating barge and comprises spaced buoyantmembers, one of which is positioned at or adjacent tothe base of thetower, said method comprising floating the tower in a horizontalposition, then ooding a buoyant member at or adjacent the base of thetower to bring said tower to a vertical partly submerged position, andmanipulating the tower, asthe ooding of said buoyant member iscontinued, or the flooding of another buoyant member is commenced, tosettle the tower downwardly and to bring the base to rest on the bed ofthe body of water. l

20. The method oi. positioning marine towers in place, which towers maybe built-up on land or on a floating barge and which include spacedbuoyant embers, one of which is Vpositioned at or adjacen to the base ofthe tower, said method comprising disposing the tower upon the bargehorizontally, then transporting the barge to the general,V area wherethe tower is to be located, then discharging the tower from the bargewhile thetower is in a horizontal position thereon whereby the towerbecomes aoat in a maneuverable horizontal position, then ooding thebuoyant member at or adjacent the base of the tower to bring said towerto a vertical partly submerged position, and settling the towerdownwardly by further ooding said buoyant members or one of said buoyantmembers to bring the base of the tower to rest on the bed of a body ofwater.

, `21. The method of positioning marine towers in place, which Vtowersmay be built-up on land or on a, floating barge and which comprisesspaced buoyant members, one of which is. positioned at or adjacent thebase of the tower, and which said barge is` provided with at least onecontrol/buoyant membensaid method comprising disposing the tower uponthe barge horizontally, then transporting the barge to the general areawhere thel tower is to be located, then iiooding said control buoyantmember orfvsaid barge to tilt said barge for discharging the towertherefrom whereby the The following references are ofV record in the Yof said tower, or another of said buoyant membersV o f said tower,continues to further settle the. Vtower-bringing the base of the towerto rest on the bed ofthe body of water. 1

22. The method of Vpositioning marine towers in place as set forth inclaim 19, further comprising selectively islackening .and/or tighteningremotely anchored guy means connected with the tower to adjust andmaintain the tower to and in substantially perpendicular position,during the period the tower has assumed a vertical position by floodingcertain of said buoyant members and is settling to water-bed; andLthereafter, for adding to the stability of the Jtower and raid inmaintaining the same in ayvertical position in times of extreme stress.

GEORGE L. KIRBY.-

REFERENCES CITED iile of this patent: I 'Y Y UNITED STATES PATENTS YNumber Name A Y Date 2,248,051 Armstrong July 8, 1941 `1,856,312Bradshaw` May 3, 1932 2,210,408 Henry s Aug. 6,V 1940 1,681,533 IGilliasso Aug. 21, 1928

